WO/2005/059618 is referenced by 409 patents.

Very high aperture microlithography projection objectives operating at the wavelengths of 248 nm, 193 nm and also 157 nm, suitable for optical immersion or near-field operation with aperture values that can exceed 1.4 are made feasible with crystalline lenses and crystalline end plates P of NaCl, KCl, KI, RbI, CsI, and MgO, YAG with refractive indices up to and above 2.0. These crystalline lenses and end plates are placed between the system aperture stop AS and the wafer W, preferably as the last lenses on the image side of the objective.

Title
Microlithography projection objective with crystal lens
Application Number
PCT/EP2004/014290
Publication Number
2005/059618
Application Date
December 15, 2004
Publication Date
June 30, 2005
Inventor
Clauss Wilfried
Schuster Karl Heinz
Agent
M√úLLER RISSMANN Werner
Assignee
Clauss Wilfried
Schuster Karl Heinz
Carl Zeiss Smt
IPC
G03F 07/20
G02B 19/00
G02B 13/14
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